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arXiv · 1703.03911

The SNR Puppis A Revisited with Seven Years of Fermi Large Area Telescope Observations

Yu-Liang Xin·Xiao-Lei Guo·Neng-Hui Liao·Qiang Yuan·Si-Ming Liu·Da-Ming Wei
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Abstract

Puppis A is a very famous and extensively studied supernova remnant (SNR) that shows strong evidence of shock-cloud interaction. We re-analyze the GeV $γ$-ray emission of it using seven years Pass 8 data recorded by the Fermi Large Area Telescope (Fermi-LAT). The morphology of the $γ$-ray emission is more compatible with that of the thermal X-ray and IR emissions than the radio image, which suggests a possible correlation between the gamma-ray emitting region and dense clouds. The $γ$-ray spectrum in the energy range of 1-500 GeV shows a break at $7.92\pm1.91$ GeV with the photon indices of $1.81\pm0.08$ below the break and $2.53\pm0.12$ above the break, which can naturally explain the lack of TeV $γ$-ray emission from Puppis A. The multi-wavelength observations favor a hadronic origin for the $γ$-ray emission.

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Yu-Liang Xin, Xiao-Lei Guo, Neng-Hui Liao, Qiang Yuan, Si-Ming Liu, Da-Ming Wei. 2017-05-22. The SNR Puppis A Revisited with Seven Years of Fermi Large Area Telescope Observations. https://doi.org/10.3847/1538-4357%2Faa74bb

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